dac connections?

What the different with RCA vs Coax input on an DAC, also on the DAC it has a Toslink connection do you need to use the coax with it?.

I have Fiio Dac D03K. This is all new to me so I know nothing about this, so what I like to do is connect my computer to a receiver and listen to youtube and tunein radio from the receiver with my headphones. The dac has one RCA and a Optical cable input, the computer don't have RCA or Optical...

I'm trying to find a sensible response to what seems to be a basic question: what happens when I plug a cell phone into an outboard DAC using an USB C cable? Let's walk the path through, at a high level: QuBuzz - > Android OS - > .... - > Outboard DAC The big question is, what happens to the...

Somewhat confused…so the question (s) about an external DAC for a CD player/transport; as I've continued to research the possibility of getting an external DAC and trying to understand them: When using a Digital optical/coaxial connection, you're just sending bits to your Receiver's DAC, so...